Dental impression tray



G. s. MNSQN DENTAL IMPRESSION TRM Filed July 31, 192,0'l

[7m/enfer GEORGEAMoA/JON la@ wf( ATTORNEYS Patented pr. 3, 1923.

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GEORGE S. IVIONSON, OF ST. PAUL, MINNESOTA.

DENTAL IMPRESSION TRAY.

Application filed Tuly 31,

To all whom t may concern.'

Be it known that I, GEORGE MoNsoN, a citizen of the United States, resident of St. Paul, county of Ramsey, State of Minnesota, have invented certain new and useful Improvements in a Dental Impression Tray, of which jdie following is a specification.

In the practice of dentistry, it is customary to provide a tray having a concave surface on one side and a handle or finger grip by means of which the tray is inserted into the mouth. The concave surface is adapted to receive a plastic material which is forced against the roof of the mouth by the pressure of the tray for the purpose of making an exactreproduction of the roof of the mouth in the plastic, from which reproduction a plate for use with artificial teeth is manufactured.

It is essential in taking this impression that the tray be held evenly and a uniform pressure be exerted thereon in the lines of stress that ultimately the dentures will be forced to assume in the act of mastication. Unless this is done, the tray is apt to tilt or turn in the fingers, resulting in an accurate impression being taken of the roof of the mouth and consequently a poor fit for the plate when it is in ade.

The object of my invention is to provide means in connection with the tray which will insure a uniform upward pressure thereof and in consequence a perfect reproduction or impression of the roof of the mouth in the plastic contained in the tray.

The invention consists generally in various constructions and combinations, all as hereinafter described and particularly pointed out in the claims.

In the accompanying drawings forming part of this specification.

Figure l is a top view of a tray embodyino my invention,

' 4igure 2 is a bottom view of the same,

Figure 3 is a sectional view on the line 3 3 of Figure 1 showing the depth and position of the finger or thumb grip therein.

In the drawing, 2 represents the tray of the usual size and shape, made preferably of metal, having a concave upper face 3 with a centrally arranged raised or arch por- 1920. Serial No. 400,325.

tion 4. This face is filled with a suitable plastic material in which the reproduction or impression of the roof of the mouth is formed.. Un the underside and projecting from one end of the tray is a short handle 5, usually found on devices of this kind. This handle is grasped by the user of the device and the tray held in the roof of the mouth and forced upwardly to make the desired impression in the plastic. To insure the accurate seating of the tray and a uniform upward pressure thereon at all points, I provide on the underside a finger seat such as a thumb or finger impression 6 having a concave surface 7 which forms a continuation of the under surface of the handle and enclosed by a rib or ange 8 which serves to hold the thumbor finger in the depression of the grip and insure its accurate seating therein and a uniform pressure at all points on the walls of the tray. I have found from actual practice that an impression can be made with this device very quickly and with far more accurate results than has been found to be possible in trays of this kind as ordinarily made.

The finger or thumb grip may be formed in any suitable way in the bottom of the tray, it being essential of course, that it be inline with the center of the handle and opposite the center of the impression surface of the tray.

I claim asmy invention:

L. A dental impression tray having a concave upper surfacewith a centrally arranged raised portion and adapted to receive a plastic material in which the impression of the roof of the mouth is formed, one end of said tray having a handle on the underside thereof and the under surface of said tray having a concave tin-rer seat at the end of said handle and forming substantially a continuation of the surface thereof, said finger seat being adapted to receive the thumb or finger and insure uniform upward pressure at all points on the walls of the tray.

2. A dental tray, including a tray and a handle therefor, and said tray having its under face inward of the handle provided 'with a depression forming a finger hold.

3. A dental tray having a concavty on rounded and its sides being also slightly its under face whose sides and outer walls rounded upwardly and outwardly, a Conare surrounded by flanges. tnuous flange surrounding the sides and 10 4. A dental tray having a ooncavty on the said inner end. 5 its under face adjacent to `its rear which In witness whereof I have hereunto Set gradually increases n depth from its outer my hand this 26th day of July, 1920. to its inner end, its said inner end being GEORGE S. MONSON. 

